IVE TRIED ALOT OF OIL OVER THE YEARS IN MY AIRCRAFT MOTORS , AEROSHELL , PENNZOIL AIRCRAFT ,EXXON AIRCRAT OIL . PERSONALLY I THOUGHT THE PENNZOIL AIRCRAFT WAS THE BEST , IT SEEMED TO BURN LESS AND NOT BREAK-DOWN AS QUICK BUT YOU COULD ONLY GET IT AT CONGRESS AUTO AND THEN THEY QUIT CARRYIN IT.NOW IM HEARING ABOUT CASTROL AIRCRAFT OIL AND WAS WONDERING IF ANYONE HAS TRIED IT YET IN THERE AIRCRAFT ENGINES ? IM FIXING TO ORDER SOME AND GIVE IT A SHOT. I LIKE THEIR AUTOMOTIVE OILS HOPEFULLY ITS THE SAME WITH THEIR AVIATION PRODUCTS..